Most wouldn't consider that an aggressive portfolio. But Rosenberg, who served as Merrill Lynch's chief economist from 2002 to 2009, has come a long way from his 2019 recession prediction.

He even likes widely-held tech stocks.

"You could almost argue Microsoft in a way has almost become a utility. You can look at Amazon, [in the] same sort of way," added Rosenberg. "There are some companies here that you would think as being say cyclical in orientation, but actually emerged here as things that we need."

Rosenberg may be softening his negative stance, but he acknowledges the economic recovery will be rough.

"It's reasonable to assume the eye of the storm is this quarter, and that we're going to get a recovery in fits and starts probably for the next year," he noted. "It's going to be a very feeble recovery, and I think what happens is the market will run ahead of itself."

'Turn bullish in a heartbeat'

He adds there's one vital factor that would push him squarely into the bull camp.

"This big bear would turn bullish in a heartbeat if a vaccine were right around the corner," Rosenberg said. "We get a vaccine, it's a total game changer."